The invention relates to photography and photographic cameras and more particularly relates to camera frame assemblies having an independently back-pivoting drive hub for an impact shutter.
One-time-use cameras and other simple cameras commonly use an impact shutter. These shutters are operated by a shutter driver (sometimes called a xe2x80x9chigh energy leverxe2x80x9d) that strikes a tang or shoulder of a shutter blade. The shutter driver can slide, but is more typically rotated to strike the shutter blade. The shutter driver is spring operated and is charged by the winding of a film transport and winding mechanism that advances film simultaneously with moving the shutter driver to a charged position. These functionalities make it convenient to provide the shutter driver near the film. On the other hand, the shutter is most conveniently placed at some distance from the film at the end of a baffle enclosing the cone of light entering through the taking lens. This distance has to be spanned, for the shutter driver to impact the shutter.
After the shutter has been opened by movement of the shutter driver from a charged position to a discharged position, the shutter driver must be recharged for the next picture taking event, by returning to the charged position from the discharged position. In striking the shutter, the striker of the actuator driver moves in a plane that parallels both a pivot axis of the shutter and the optical axis of the taking lens of the camera. During recharging, the striker moves in the same plane and the shutter moves out of the way. In many one-time-use cameras, the shutter is tilted or translated out of alignment with the pivot axis. For example, U.S. Pat. No. 5,614,975 discloses a camera, in which the shutter blade has a large slot that receives a post extending outward from the frame. During recharging, the striker pushes the shutter, moving the post along the slot and the shutter out of alignment with the pivot axis. This approach risks light leakage when the shutter is moved.
U.S. Pat. No. 5,721,995 discloses use of a series of links to trip a pair of impact shutter blades.
It would thus be desirable to provide an improved camera frame assembly in which the shutter driver recharging presents a reduced risk of light leakage due to shutter movement.
The invention is defined by the claims. The invention, in broader aspects, provides a camera frame assembly has a base member and a drive hub connected to the base member. A shutter is joined to the drive hub. A shutter driver is mounted to the base member. The shutter driver selectively deflects from a charged state to a discharged state and impacts the drive hub during the deflecting. The drive hub and shutter pivot together relative to the base member in a discharge direction about the pivot axis, responsive to the impacting, from a shutter closed position to a shutter open position. The drive hub is pivotable, in a recharge direction opposite the discharge direction, independent of the shutter.
It is an advantageous effect of the invention that an improved camera frame assembly is provided in which the shutter driver recharging presents a reduced risk of light leakage due to shutter movement.